As materials for forming inorganic patterns, there have been known photosensitive pastes made up with a photosensitive resin filled with or comprising inorganic particulates. Such photosensitive paste is coated or applied on a substrate (or base), and the coat layer is exposed patternwise through a given mask, developed, and baked or calcinated for eliminating an organic component(s) to form an inorganic pattern. Photosensitive pastes of such type are required to have a high inorganic component content and high sensitivity, and to be able to give high resolution. However, in a photosensitive paste, the concentration of inorganic particulates (filling factor) and photosensitive properties (e.g., sensitivity, resolution) are incompatible with each other. Therefore, when the filling factor of the inorganic particulates is low, upon heat-baking for elimination of organic components, an inorganic pattern largely shrinks or becomes much smaller in volume and is separated from the substrate, resulting in deterioration in adhesion. In addition, the profile of the pattern is deformed and the resolution is consequently deteriorated. On the other hand, when the content of the inorganic particulates is raised, exposed light is absorbed, reflected or scattered by the inorganic particulates and therefore the sensitivity and resolution are reduced. Moreover, it is difficult to form minute inorganic patterns having highly rectangular profiles and high aspect ratios with high precision using the above photosensitive paste.
To improve the dispersibility of inorganic particulates and thereby to improve the sensitivity and resolution, treatment over the surfaces of the inorganic particulates has been proposed. However, the dispersibility has not reached a sufficient level yet and the contrast between the exposed areas and non-exposed areas (the difference between the solubilities thereof to a developer) is low, and such surface treatment is not sufficient as to improve the resolution.
Accordingly, an object of the present invention is to provide a inorganic substance-containing photosensitive resin composition which is highly sensitive and capable of providing an inorganic pattern of high resolution even with a high inorganic component content, a process for producing the same, and a process for forming inorganic patterns.
Another object of the present invention is to provide an inorganic substance-containing photosensitive composition useful for forming an inorganic pattern which shows a sharply defined rectangular profile and has a high aspect ratio, a process for producing the same, and a process for forming inorganic patterns.